US3662589A
Expired / Lapsed
US
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Ultrasonic flaw determination by spectral analysis
Assignee: United States Atomic Energy Commission
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Filing: 1971-02-02
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Granted: 1972-05-16
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Expires: 1991-02-02
Abstract
Abstract A method of quantitatively determining the size and orientation of flaws within a material. A broadband pulse having a frequency width of at least several MHz is used for an input pulse from a transducer which is directed toward the test material which may contain a flaw, and the average frequency interval between interference maxima in the reflected spectrum is relatable to both the size and orientation of the flaw. An experimental method using two known angle changes allows determination of the size and angle of randomly oriented discontinuities within metal specimens.
Inventors
- 👤 Laszlo Adler
- 👤 Hubert L Whaley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:31
CPC Classifications
G; G01; G01N; G01N29/00; G01N29/34; G01N29/348; G01N2291/00; G01N2291/02; G01N2291/028; G01N2291/0289
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
207 words
A nondestructive method for determining the size and orientation of a randomly oriented flaw within a material sample comprising the steps of generating an ultrasonic pulse having a wide frequency spectrum by a transducer, receiving with the same transducer ultrasonic signals reflected from any flaw in said sample in close proximity to said transducer, analyzing the frequency spectrum of the reflected signals to determine a first average frequency interval between points of maxima in the reflected spectrum, recording said first average frequency interval, displacing the transducer a first selected angle in a first plane from its first position with respect to the sample and then repeating the above steps to determine a second average frequency interval between points of maxima in the second reflected spectrum, recording said second average frequency interval, displacing the transducer a second selected angle in a second plane and from said first position with respect to said sample and then repeating the above steps to determine a third average frequency interval between points of maxima in the third reflected spectrum, recording said third average frequency interval, and finally utilizing the recorded average frequency intervals obtained for all positions of said transducer for determining the size and orientation of the flaw in said sample.
Claim 2
Dependent Claim
207 words
A nondestructive method for determining the size and orientation of a randomly oriented flaw within a material sample comprising the steps of generating an ultrasonic pulse having a wide frequency spectrum by a transducer, receiving with the same transducer ultrasonic signals reflected from any flaw in said sample in close proximity to said transducer, analyzing the frequency spectrum of the reflected signals to determine a first average frequency interval between points of maxima in the reflected spectrum, recording said first average frequency interval, displacing the transducer a first selected angle in a first plane from its first position with respect to the sample and then repeating the above steps to determine a second average frequency interval between points of maxima in the second reflected spectrum, recording said second average frequency interval, displacing the transducer a second selected angle in a second plane and from said first position with respect to said sample and then repeating the above steps to determine a third average frequency interval between points of maxima in the third reflected spectrum, recording said third average frequency interval, and finally utilizing the recorded average frequency intervals obtained for all positions of said transducer for determining the size and orientation of the flaw in said sample.
Claim 3
Dependent Claim
172 words
The method set forth in claim 1, wherein said first average frequency interval is designated Delta f, and wherein said first interval may be expressed by the equation: where: Vm velocity of sound in the sample in which it is propagating when the reflecting surface is encountered; Theta 1 orientation of the flaw in said first plane with respect to a coordinate system; Theta 2 orientation of the flaw in said second plane perpendicular to said first plane with respect to said coordinate system; d diameter of said flaw; and further wherein said second average frequency interval is designated Delta f1 and said third average frequency interval is designated Delta f2, said Delta f1 may be expressed by the equation: where Phi 1'' is equal to said first selected angle, said Delta f2 may be expressed by the equation: where Phi 2'' is eqUal to said second selected angle, whereby the unknown values of d, Theta 1, and Theta 2 are determined by solving said equations simultaneously by means of a computer.
Claim 4
Dependent Claim
34 words
The method set forth in claim 2, and further including the step of determining said points of maxima in said reflected spectrum for each position of said transducer by an electronic frequency spectrum analyzer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-16 | 1975-11-15 | 1976-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-16 | 1979-11-15 | 1980-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-16 | 1983-11-15 | 1984-05-16 | $7700.00 | Window Closed / Lapsed |